Technical Abstract:
Resistance in peas to Aphanomyces euteiches has previously been measured by counting oospores in infected root tissue, disease severity ratings, and/or yield in disease nurseries. In a controlled environment, differences in rate of lesion development in resistant and susceptible pea lines is evident and repeatable. Indirect ELISA with a polyclonal antiserum, with increased specificity for oospore antigens, of tissue within the lesion revealed a positive, linear correlation (r**2 = 0.86) between lesion length and ELISA readings at 405 nm. Resistance in peas to A. euteiches appears associated with slower lesion development and pathogen buildup in pea roots and is inheritable.